Whilst there is a version that is different, I have seen the Cumana schematics written out (almost) exactly the same as Microdisc.
It's led me to believe Cumana had a hand in designing the Microdisc.
Initially the Cumana interface ROM had to use CumanaDOS but the V2 version is compatible.

The schematics I have which show the Microdisc board show a rectangular circuit board. As you'll see from George's picture, the Microdisc board is not rectangular but has 'cut-outs'.

Schematically Cumana and Microdisc are similar. The main difference is in address buffernig and the clock divider. I prefer the microdisc pcb-edges, because I have microdisc to repair as I've told. But I have not full success, because my plate is a little longer. So it fits in the box, but must be isolated from the metal holders under the board. I like Cumana design, because it saves the Oric expansion port, so you could connect some additional devices. Maybe I'll try to make some Cumana replica in the future, but I will concentrate to new Pravetz 9D design for now:http://forum.defence-force.org/viewtopic.php?f=23&t=954

I don't thing it's not working. I thing to make some RS-232 board and will understand, but schematically everything is correct and the board is very good, there's no reason to not working. Will try and will say.

I remember when they used to use a modem to connect to other computers via the phone line. (Bulletin boards.)
The Oriccomms software was used on disk, but because the disk interface was in place, the modem couldn't be connected so they used to mount another socket on the cable between the Oric and disk interface.

The expansion port may be for additional devices that may require an external VIA. I have just come across description and diagrams to make this for the Oric-1. (It's basically another 6522 plus a few components.) I think it was for controlling robots etc.

It looks like it might be copied from another source, maybe a Penfold book, (he wrote a lot of electronics books in the UK), but the typing is laid out in the same sort of way as some of the other technical material from Oric.

Hello guys.
There are 6 controllers ready. I'll prepare additional 4 these days. Some of them are reserved, but there are 6 available for new owners. If someone need a controller let me know via PM.
Regards

As an Oric newcomer could you clarify exactly what this offers for a standard Atmos please? Am I able to use it in conjunction with an HxC floppy emulator (which I already have) in order to load and save floppy images to/from an SD card? Or do I need some additional disc controller for the Atmos itself?

Sorry for the naive questions!

Last edited by AndyGarton on Tue Jul 16, 2013 4:44 pm, edited 1 time in total.

AndyGarton wrote:As an Oric newcomer could you clarify exactly what this offers for a standard Atmos please? Am I able to use it in conjunction with an HxC floppy emulator (which I already have) in order to load and save floppy images to/from an SD card? Or do I need some additional disc controller for the Atmos itself?

The controller works fine with HxC emulator (I thing to make a clip these days). It don't need additional plate - just connect it to Oric via ribbon cable and boot.

barnsey123 wrote:Is external PSU required? If so, what do we need?

You need only usual PC PSU - the connector is from PC world.

As you can see all the chips are on sockets, so the controller is very easy to repair if it needs somewhere in the future

Last edited by jorodr on Tue Jul 16, 2013 5:49 pm, edited 1 time in total.

That's actually something important to mention, because I believe the connector on the Microdisc board has swapped around colors despite having the same connector.

These controllers are for using alone, not for replacing a board at the Microdisc case. Because of a Greek Oric friend I'm making next 4 plates just to put in the Microdisc case. So it's important to know who what kind of PSU connector wants

Because of the interests of the controllers they are almost clear and I must order another 10-15 boards set. But I want to tell something to every who want the controller. DBug told me in it's private message when he ordered the controller that his original Microdisc work only with Pravetz 8D, but not with Oric Atmos and Oric 1. So there's a chance my controller to not work with every Oric on the Earth and I will refund the money, but the buyer must pay the shipping back (about 10 euros). All of the controllers are hard tested on 4 Orics and they work reliable. If your Oric don't work with the controller please contact with me to find the problem. You know that the Oric bus is complicated, but more of the cases the problem is with light turn the RV1 trimmer. If you have some questions I'll be glad go answer.